Bruce McGibbon Snippet A

Bruce McGibbon describes a field trial he conducted with the Canadian Armed Forces in Shilo, Manitoba. One morning, three teams of fifteen men were given hearing tests. One group was given ear muffs and ear plugs, the second only ear plugs, and the third was given no protection and ordered not to cover their ears – the standard protocol of the day. After a four-hour barrage, the men were retested: the first group had no change but two of the fifteen in the third group had permanent hearing loss. The CAF subsequently changed their protocol!